16:00:21 #startmeeting Mistral 16:00:25 Meeting started Mon Jun 6 16:00:21 2016 UTC and is due to finish in 60 minutes. The chair is rakhmerov. Information about MeetBot at http://wiki.debian.org/MeetBot. 16:00:26 Useful Commands: #action #agreed #help #info #idea #link #topic #startvote. 16:00:28 The meeting name has been set to 'mistral' 16:00:37 hi all 16:02:00 still waiting for people to join 16:02:07 Hi 16:02:10 hparekh_: hey 16:02:16 Hey 16:02:25 hello (first time here) 16:03:33 hi guys 16:04:12 ok, let's skip our traditional "Review Action Items" topic since last time there was a very few people 16:04:34 #topic Current Status by team members (current activities, roadblocks etc.) 16:04:59 Hi 16:05:01 my status: still finishing up refactoring of Mistral engine components 16:05:04 mgershen: hi ) 16:05:40 My status: Just reviewed some patches and worked on policy related blueprint. 16:05:49 in parallel I started writing a spec for Custom Actions API: https://review.openstack.org/#/c/325769/ 16:05:53 Hi rakhmerov, I'm working on some internal stuff. I hope to finish by next week. 16:06:04 hparekh_: how is that BP going? policy 16:06:16 mgershen: yes, I know :) It's ok 16:06:33 mgershen: ping me when you finish, there's a number of things to work on 16:07:15 its almost finished will post patch soon working. Actually I am working on tests 16:07:27 hparekh_: very cool 16:07:33 looking forward to see it 16:07:34 d0ugal, jpeeler: can you guys say a couple of words about your involvement with Mistral and how you would like to participate? 16:08:08 if you want ) 16:08:16 I have been working on TripleO for a while and want to help improve Mistral to aid the TripleO use-case. 16:08:37 d0ugal: do you work together with Ryan? 16:08:50 rakhmerov: Yeah, me rbrady and jpeeler work together :) 16:08:51 i believe i will also be supporting the tripleo use case as well 16:08:55 ok 16:09:01 I see 16:09:28 but hopefully we can just help out in general too! 16:09:30 but i hope to fix generic mistral bugs and such too 16:09:32 right 16:09:47 I know that rbrady has been interested in that Custom Actions API since we found that this part is not really designed well enough in Mistral 16:10:05 ooh, I see 16:10:34 well, ok. Then I'd like to ask you to participate in that spec that I pointed to when it's finished 16:10:55 https://review.openstack.org/#/c/325769/ 16:11:09 because I guess that should be pretty important for you 16:11:34 rakhmerov: +1, I'll take a look 16:11:47 and as far as other stuff, would you like me to assign something relatively simple to you or you think you know Mistral well enough to be able to approach something more serious? 16:11:59 like new feature or serious improvement 16:12:07 rakhmerov: Sure, I would be happy to take something simple. 16:12:14 d0ugal: ok 16:12:21 I would like to do something more serious, but I am not sure yet how much time I can dedicate to Mistral 16:12:23 then I'll do it offline 16:12:27 Great 16:12:48 yeah, and feel free to communicate on whatever is needed to complete that 16:13:01 ok, thanks guys 16:14:13 ok, I actually also planned to talk a little bit about Custom Actions API 16:14:21 rakhmerov: OK np, I'll ping you when I'll be free. 16:14:26 ok 16:14:34 #topic Custom Actions API 16:15:30 so, maybe it's a little too early to talk about it but anyway, I'll just tell some basic info for now, maybe you'll have something to say at this early stage too 16:16:10 generally, the background comes from the need to write new actions which essentially Python classes inherited from mistral.actions.base.Action 16:16:27 it has essentially method run() that needs to be implemented 16:17:13 the problem is that so far most of our users and customers have been writing custom actions that weren't related with OpenStack 16:17:27 they didn't require any serious integration with OpenStack 16:17:41 in this case implementing them is pretty straightforward thing to do 16:18:48 but, in TripleO team wants to write new actions that could leverage other OpenStack services and hence use things like security context that an action is running in 16:19:39 we already provide actions for accessing OpenStack services the attempt was made to do something similar for other actions 16:20:12 by using modules like mistral.context that provides basically with auth token, project, user 16:20:34 however, we never considered this module as a stable thing that all actions developers could use 16:21:01 long story short, we need to establish a Python API for developing new Mistral actions 16:21:44 as I see it, it should provide access to security context (user, project, token), workflow context (workflow execution id, task id, action id etc.) 16:21:47 at minimum 16:22:15 and other useful things that may simplify actions development 16:22:29 like, for example, ability to reuse other actions that already exist 16:22:36 some kind of composition 16:23:12 so that we can do something like: action_utils.get_action("nova.servers_get").params(1,2,3).run() 16:24:15 there's also need to explicitly define some data types that are serializable and can be used on executor side 16:24:24 like mistral.worfklow.utils.Result 16:24:31 that actions are allowed to return 16:24:53 dprince: Have you seen this Mistral WIP spec? https://review.openstack.org/#/c/325769 16:25:06 dprince: We are just talking about it now. 16:25:11 d0ugal: unlikely, I just started it today 16:25:12 :) 16:25:15 oh :) 16:25:28 so, other things that we probably need to do as well is to move existing OpenStack actions into a separate repo 16:25:51 rakhmerov: I know that rbrady would like to write a spec for moving the actions 16:26:00 to be able to work on them separately and implement a script to be able to install only subset of them 16:26:10 d0ugal: ok, yes 16:26:32 d0ugal: I'm just wondering whether it should be a new spec or we can do it as part of this one? 16:26:46 at first glance, it should be a new spec 16:26:54 rakhmerov: Good question. 16:27:11 I am not sure how complex it is, but I would agree that a new spec makes sense 16:27:16 It is related, but different enough. 16:27:18 and btw, that Custom Actions API, in my opinion, should be moved to a different subproject 16:27:29 subproject? 16:27:30 d0ugal: yep 16:27:38 Like it's own repo? 16:27:38 yes, that is why.. 16:27:42 right 16:27:46 +1 16:27:51 the reason is the following: 16:28:29 Having a standalone Python library is much clearer than making part of a large codebase a public Python API. 16:28:35 these interfaces(sorry, my old Java habit to think in interfaces for key abstractions) and classes can be used by both engine and executor 16:28:46 d0ugal: yes, exactly 16:29:00 +1 agree 16:29:10 ideally, we should be even able to package Mistral executor separately 16:29:20 with as few dependencies as possible 16:29:34 because it's supposed to be lightweight and very simple 16:30:20 and one of those dependencies should be something like mistral-common (need to think about naming) where all that Custom Actions API should live 16:30:49 and if Mistral engine (server side) needs those things too it can also have that dependency 16:31:11 thoughts? 16:31:58 :) hopefully it all makes sense 16:32:05 I think it sounds great. 16:32:12 I don't like the name mistral-common 16:32:20 yeah 16:32:29 I don't want to bikeshed that now, but we have tripleo-common and IMO it was a mistake 16:32:48 what was it for? 16:32:59 That is the problem :) The purpose isn't clear 16:33:04 what was your initial idea of it? 16:33:08 so it has everything in it 16:33:10 aah 16:33:12 yeah 16:33:21 I see, yes 16:33:24 The initial idea was common code between the CLI and API. However, plans changed 16:33:39 maybe we need to make it serve a certain purpose, yes, for clarity 16:33:44 +1 16:33:53 like mistral-actions-lib, dunno 16:34:05 mistral-actions might be enough 16:34:18 d0ugal: looking 16:34:24 yep, may be 16:34:32 dprince: hi Dan 16:34:38 Our Mistral actions (and workflows) are in tripleo-common, I would like to move them to tripleo-workflows (a new repo) eventually. 16:34:48 ok 16:35:01 mistral-actions mistral-actions-lib are both good IMO 16:35:35 mgershen: +1 16:35:46 mistral-actions may be slightly confusing if we want to make it a lib for developing actions but not for actions themselves 16:35:54 d0ugal: I like the idea. I think it is based on feedback that Ryan and I gave to Renat at the summit 16:36:10 as far as actions themselves, like OpenStack actions, we could use mistral-extra that already exists 16:36:17 dprince: Yes, I think so. That is why I thought you might have an opinion :) but I guess you need time to read it 16:36:42 d0ugal: yeah. I'll read it more carefully :) 16:36:45 dprince: yes, I'm now trying to aggregate all thoughts on this and write up an initial spec 16:37:01 d0ugal: I like the idea of tripleo-workflows too 16:37:21 d0ugal: FWIW I initially organized it like this last year but people weren't buying it at the time: https://github.com/dprince/tripleo-mistral-workflows 16:37:58 what were they saying on that? 16:38:01 why not? 16:38:15 rakhmerov: I think it was just to early to debate where things lived at the time 16:38:22 ok 16:38:37 Yeah, I don't even remember the location being in the discussion :) 16:38:40 d0ugal: that said, I would like to see us make it work ASAP... and actually wire it in soon 16:38:46 d0ugal: regardless of where it lives 16:39:05 ok, so early feedback would be appreciated (I mean that spec) 16:39:10 dprince: +1 16:39:16 I'll try to finish it asap 16:39:21 ideally tomorrow 16:39:22 rakhmerov: absolutely, thanks for that 16:39:33 with as many details as I can come up with at this stage 16:39:41 rakhmerov: I'll review tomorrow morning, I don't have much time left today. 16:39:44 dprince: no problem, I know that it's a pain 16:39:59 d0ugal: no problem, thanks 16:40:36 d0ugal, jpeeler: you guys are very welcome 16:40:48 I hope you'll enjoy working with us ) 16:41:08 Thanks, I am looking forward to it. Mistral is a neat project! 16:41:09 thanks /me is still getting started 16:41:21 I'll try to assign something to you tomorrow (it's almost midnight here in Siberia :) ) 16:41:40 that's all from my side on that topic 16:41:57 if you'd like to add something pls go ahead 16:42:01 rakhmerov: wow, that is late :) 16:42:07 for me it seems like we're on the same page 16:42:15 Yes, I think so. 16:42:18 d0ugal: yeah, but it's ok, I'm used to it 16:42:31 I'm sure rbrady will also review the spec 16:42:41 I plan to :) 16:42:45 can afford being a little late for work tomorrow morning :) 16:42:58 rbrady: hi Ryan ) 16:43:05 yes, please 16:43:12 it's not finished yet though 16:43:19 ok 16:43:24 #topic Open Discussion 16:44:16 one more thing that I'd like you to have a look at is the scope for Newton-2 16:44:17 https://launchpad.net/mistral/+milestone/newton-2 16:44:44 if you want to add something to it, it's a high time you did that ) 16:44:56 for example, if something is very much needed 16:45:04 bugs and blueprints 16:45:51 rakhmerov: hi, so has anybody every proposed an idea around on_fail error handling 16:46:12 dprince: what's that? 16:46:13 rakhmerov: like we have on_error... but it doesn't handle the case where an unhandled exception is thrown 16:46:39 dprince: ooh, you mean errors not related to action execution? 16:46:44 rakhmerov: I think it is a corner case rbrady and I hit in the past few weeks 16:47:04 rakhmerov: perhaps, this would be like an unhandled stack trace from any action 16:47:10 rakhmerov: on_error doesn't get it 16:47:25 It's a bit like in unittests, they can pass, fail or error. 16:47:30 dprince: yes, right. It only handles "expected" errors provided by actions 16:47:43 rakhmerov: normally how I debug this is by looking at the Execution result itself 16:47:45 hm.. interesting 16:47:51 yes 16:47:58 rakhmerov: it is an idea and I think we are perhaps missing something here 16:48:10 may be, yes 16:48:17 need to think about it 16:48:30 rakhmerov: our use case is we'd like to make sure that all errors (or failures) get Log a zaqar message accordingly 16:48:31 share your thoughts on this 16:49:34 rakhmerov: I think we could draft up a spec around the problem and perhaps better approach it from that angle 16:49:56 dprince: well, at the first glance, from engine perspective it's not a big deal to handle such failures 16:50:01 rakhmerov: but the general idea was encountered while rbrady and I were pair pramming to write these https://review.openstack.org/#/c/300200/10/workbooks/baremetal.yaml 16:50:08 dprince: yes, that would be helpful 16:50:48 rakhmerov: cool, Yeah when I looked at the engine and how exceptions are already caught I don't think this is a big change 16:51:03 rakhmerov: we'd just want to get the interface around it correct 16:51:09 rakhmerov: another idea for you 16:51:11 dprince: I'm now actively making it much much simpler 16:51:40 dprince: honestly, we had this part slightly messy bit it's not getting improved 16:51:41 rakhmerov: has anyone ever proposed the idea around passing input parameters via on_error/on_complete/on_success? 16:51:46 I mean how we handle errors 16:52:14 rakhmerov: like it would be super cool to be able to re-use a generic error handler by passing parameters to it 16:52:23 dprince: yes, I guess you mean something like https://blueprints.launchpad.net/mistral/+spec/mistral-explicit-task-parameters 16:52:31 have a look 16:52:36 I guess this is it 16:53:11 rakhmerov: okay, so this would be acceptable it seems like 16:53:19 rakhmerov: just hasn't been implemented yet :) 16:53:22 * d0ugal needs to run, thanks for the meeting. I'll catch up with the end in the notes. 16:53:23 hparekh_ has already made some preparation steps towards that BP as part of another BP 16:53:25 rakhmerov: opportunity 16:53:32 dprince: right 16:54:07 dprince: although, this thing is slightly ambiguous 16:54:21 if we look into details 16:54:48 not even ambiguous, we basically need to define its semantics well 16:55:10 like what do those parameters mean exactly? 16:55:31 I see it as just a shortcut for publishing variables into context 16:55:59 other opinions were different 16:56:25 like we should run such tasks in some isolated data context if we explicitly pass parameters 16:57:05 or, another option: if we pass params explicitly then we just override values for of task action parameters 16:57:12 e.g.: 16:57:14 rakhmerov: there are some parameters in the context that aren't easy to access unless you pass them explicitly I think 16:57:15 task1: 16:57:34 action: my_param= <% $.some_yaql%> 16:57:43 rakhmerov: like the error status/message from the calling task... in a generic fashion 16:57:51 if we do task1("val") we would just ignore that yaql 16:58:09 dprince: yeah 16:58:26 so, I mean there's something to discuss on that 16:58:53 I think we need a spec actually for that, too 16:59:06 to list out those options and choose the best one 16:59:15 rakhmerov: yes, probably 16:59:32 #action rakhmerov: have someone to write a spec for explicit task params BP 16:59:40 ok, time's up 17:00:00 it was good to have you all on the meeting! 17:00:05 thanks for joining ) 17:00:08 bye 17:00:13 Thanks bye !!! 17:00:21 #endmeeting